Id like your input/thoughts

Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
I recently had gotten into a discussion , with a guy who was interested in building a custom replica car,
in which he intended to install a serious big block chevy engine,
many guys fail to realize a full race engine with its impressive power rating is both not a good choice and not likely to last for close to a 100-120 k miles,
between required rebuilds, its also not going to produce the listed power levels without constant tuning.
he was debating the best choice in displacement, and compression etc.
and he seemed to be under the impression that he could purchase a 12.5:1 compression, 572-632 bbc engine for the car,slap it and and drive it without issues.
and that the much larger displacement engine would provide him with an obvious advantage
, as those larger engines do produce impressive torque over a wide power/rpm band.
he was looking at an 800 hp 12.5:1 compression crate engine,
I pointed out, he would need a steady and expensive supply of 110 octane fuel,
and paying well over double the price per gallon for race vs pump gas,
gets old really fast on a car used for transportation.
and running out of gas ,
with a car that would be lucky to get 7 mpg,
and not being able to use pump gas is a problem.
because this was to be used 98% of the time as a performance street toy,

now keep in mind the total car weight, suspension and drive train,
and the car he was thinking of building would be used for both daily transportation
and occasional road racing, not much drag racing.
I pointed out the option of building a serious custom built engine.
but I think the need for massive torque, and need for only race fuel,
is counter productive in such a light car
(less than 2400 lbs with a BBC engine)
I suggested a DART block, and a scat rotating assembly
but , because this was not a full out race application,
and durability and no constant rebuilds would be very desirable,
a slightly lower compression than a true race engine would use, and lower displacement 540 BBC with about 9.3 :1 compression,
all forged components and a decent hydraulic roller cam, could be built to give very impressive street/strip performance,
without having to always pay for high octane fuel and he might consider a nitrous plate if he wanted exceptional power occasionally.
ID have used a dana 60 rear differential, with 3.54:1 gears and a manual transmission with OD like a super muncie
I suggested that he could easily still expect to hit 650 hp
if the correctly matched components were used, and he would have an extra 200 hp plus on tap if he chose to use the wet nitrous.
something like this, but certainly you do the math and tweak the parts selection as required.

block
http://dartheads.com/dart-product/big-m-mrk-iv-gen-v-gen-vi/

intake
https://www.jegs.com/i/Edelbrock/350/29271/10002/-1

carb
https://www.jegs.com/i/Holley/510/0-9375-1/10002/-1

heads
https://www.airflowresearch.com/315cc-bbc-rectangle-port-cylinder-head/

rotating assembly
https://www.jegs.com/i/Scat/942/1-42370BI/10002/-1

transmission
https://www.riversidegear.com/munci...g-m23-4-speed-custom-built-to-your-needs.html

hyd roller cam
https://cranecams.com/powermax-hydraulic-roller-240-248-camshaft-for-chevrolet-396-454-big-block/
crane139681.png


wet nitrous
https://www.summitracing.com/parts/nos-02002nos/overview/


cheetah1.jpg

cheetah2.jpg

cheetah3.jpg

cheetah4.jpg

cheetah5.jpg


heres an example of what might be built from a kit car that would kick butt!
new13111921292.jpg

new131119119610.jpg

new13111911656.jpg


new13111921181.jpg

tumblr_omi5br9uAg1ttxfeno1_1280.jpg

http://www.scottrodscustom.com/cheetah.html

http://garage.grumpysperformance.co...asonably-fast-in-street-trim.3404/#post-69170

http://garage.grumpysperformance.co...g-custom-car-body-suppliers.11629/#post-54275

http://garage.grumpysperformance.com/index.php?threads/muncie-transmission-info.396/#post-77950
 
Last edited:
I recently had gotten into a discussion , with a guy who was interested in building a custom replica car,
in which he intended to install a serious big block chevy engine,
many guys fail to realize a full race engine with its impressive power rating is both not a good choice and not likely to last for close to a 100-120 k miles between required rebuilds, its also not going to produce the listed power levels without constant tuning.
he was debating the best choice in displacement, and compression etc.
and he seemed to be under the impression that he could purchase a 12.5:1 compression, 572-632 bbc engine for the car,slap it and and drive it without issues.
and that the much larger displacement engine would provide him with an obvious advantage
, as those larger engines do produce impressive torque over a wide power/rpm band.
he was looking at an 800 hp 12.5:1 compression crate engine,
I pointed out, he would need a steady and expensive supply of 110 octane fuel,
and paying well over double the price per gallon for race vs pump gas,
gets old really fast on a car used for transportation.
and running out of gas ,
with a car that would be lucky to get 7 mpg,
and not being able to use pump gas is a problem.
because this was to be used 98% of the time as a performance street toy,

now keep in mind the total car weight, suspension and drive train,
and the car he was thinking of building would be used for both daily transportation
and occasional road racing, not much drag racing.
I pointed out the option of building a serious custom built engine.
but I think the need for massive torque, and need for only race fuel,
is counter productive in such a light car
(less than 2400 lbs with a BBC engine)
I suggested a DART block, and a scat rotating assembly
but , because this was not a full out race application,
and durability and no constant rebuilds would be very desirable,
a slightly lower compression than a true race engine would use, and lower displacement 540 BBC with about 9.3 :1 compression,
all forged components and a decent hydraulic roller cam, could be built to give very impressive street/strip performance,
without having to always pay for high octane fuel and he might consider a nitrous plate if he wanted exceptional power occasionally.
ID have used a dana 60 rear differential, with 3.54:1 gears and a manual transmission with OD like a super muncie
I suggested that he could easily still expect to hit 650 hp
if the correctly matched components were used, and he would have an extra 200 hp plus on tap if he chose to use the wet nitrous.
something like this, but certainly you do the math and tweak the parts selection as required.

block
http://dartheads.com/dart-product/big-m-mrk-iv-gen-v-gen-vi/

intake
https://www.jegs.com/i/Edelbrock/350/29271/10002/-1

carb
https://www.jegs.com/i/Holley/510/0-9375-1/10002/-1

heads
https://www.airflowresearch.com/315cc-bbc-rectangle-port-cylinder-head/

rotating assembly
https://www.jegs.com/i/Scat/942/1-42370BI/10002/-1

transmission
https://www.riversidegear.com/munci...g-m23-4-speed-custom-built-to-your-needs.html

hyd roller cam
https://cranecams.com/powermax-hydraulic-roller-240-248-camshaft-for-chevrolet-396-454-big-block/
crane139681.png


wet nitrous
https://www.summitracing.com/parts/nos-02002nos/overview/


cheetah1.jpg

cheetah2.jpg

cheetah3.jpg

cheetah4.jpg

cheetah5.jpg


heres an example of what might be built from a kit car that would kick butt!
new13111921292.jpg

new131119119610.jpg

new13111911656.jpg


new13111921181.jpg

tumblr_omi5br9uAg1ttxfeno1_1280.jpg

http://www.scottrodscustom.com/cheetah.html

http://garage.grumpysperformance.co...asonably-fast-in-street-trim.3404/#post-69170

http://garage.grumpysperformance.co...g-custom-car-body-suppliers.11629/#post-54275

http://garage.grumpysperformance.com/index.php?threads/muncie-transmission-info.396/#post-77950
Horsepower sells Grumpy.
That kit car would be plenty fast with 500-550 Hp.

Most people do not fully Comprehend the Torque Curve of a BBC.
Ditto for a Race Pontiac V8.

Daily driver means running on 87 octane gas to me.
Building a kit car or Replica starts at $50k.
Likely end up at 80-100k.
So he can likely afford 93 octane.
Race gas is $10 per gallon.
Guy is not a Street racer.

Cam you chose looks hot.
Roller with 82 degrees advertised valve overlap.

Turbo Boost and BBC expensive because of large cubes.
Never sell the guy a 366 BBC .
Boat anchor to most but looks interesting on paper.
Supercharged Boost Roots style most practical.
 
Last edited by a moderator:
the cam was selected to both maximize the power with the wet nitrous plate in the suggested engine,reduce detonation issues,
heads were selected to maximize results with wet nitrous,but nor restrict N/A power
AND to give the car an aggressive exhaust rumble at idle, too make the owner happy.
in a 2400 lb car he won,t be able to use the existing power given street tires, anyway.
as stated all parts are subject to further revision but the combo would work reasonably well for the intended application.
always assuming long tube heads, low restriction exhaust ,
a 8 quart baffled oil pan , large radiator and either a vertex magneto,
or individual coil per cylinder ignition.
 
Last edited:
the cam was selected to both maximize the power with the wet nitrous plate in the suggested engine,reduce detonation issues,heads were selected to maximize results with wet nitrous,but nor restrict N/A power
AND to give the car an aggressive exhaust rumble at idle, too make the owner happy.
as stated all parts are subject to further revision but the combo would work reasonably well for the intended application.
always assuming long tube heads, low restriction exhaust ,
a 8 quart baffled oil pan , large radiator and either a vertex magneto,
or individual coil per cylinder ignition.
Cam seems Hot unless for You and Me.
Just weather changes require tuning or fuel metering changes here in Midwest I know 1st hand.
People are spoiled by EFI cars and Trucks today.
Nothing sounds like a Hot Cammed engine with 454-455- 572 cubes.
Shakes the Ground.
No LS can do the same.
 
You have to be a REAL GOOD DRIVER TO USE A WET PLATE NITROUS KIT With a 2400 lb car and 500-650 Hp Big Block Chevy.
 
3R30lny.png


650 Hp BBC.
Say its a 572 ci. Very plausible on pump gas 93 octane.
250 HP shot of Nitrous.
Up t00 900 HP.

Godspeed fast.
 
It had better of at least have a C4 Corvette suspension hidden on the car.
Or 1970 Trans Am.
When they get loose only way to recover is to Power steer them back straight WOT.
Where handling is very important on the street to me.
 
Had a look at your chosen AFR 315 heads Grumpy.
It's a Racing head made for Street strip use.
Average .300 - .600 E/I ratio. Is .75-.76 :1.
Very Good.
Low lift E/I listed at .200 not so good.
.86 :1.
Intake port must be a High rise straight shot.
Wants an aggressive cam used.
 
Ok.
540 BBC.
Well known Power House.
Killer Road Race Engine.

Rod length 6.385" center to center.
Crank stroke 4.25 "
9.800 Standard deck BBC.
R/S ratio is 1.50 :1.

Best to use As a Super torque engine.
Limit Rpm to 6500.
 
Enough data is there to Engine simulate.
From our last discussion John has the most accurate simulator of the group.
I can Desktop Dyno later.

Those 540 BBC Were cranking out 950 Hp back in 1988 for John Linglefelter.
Most famous was in Big Red.
The R.J. Gotlieb driven 1969 Camaro.
Silver State Classsic.
4-speed Jerico.
2.24 diff gears in 9 inch Winston cup full floater.
Bad to the bone.
Ran 224 mph.
Average speed 190 mph for 90 miles Flat out.
Full Titanium valves by Manley.
Titanium Crower connecting rods.
Linglefeltter built 540 BBC.
ALL MOTOR.
 
With a 4.500 inch bore ignition is critical.
Coil on plug or a Vertex mag used like you stated Grumpy.

Big bore engines can be hard to light off correct.
 
Less than 2400 lb, gees that much hp, tire bill be high. I agree that much hp not needed, 500-550 at most. I drove Rick’s T bucket with 500, did a hard launch it scared the shit out of me.
 
Less than 2400 lb, gees that much hp, tire bill be high. I agree that much hp not needed, 500-550 at most. I drove Rick’s T bucket with 500, did a hard launch it scared the shit out of me.
Turbo is electronic controllable with boost controller launch like a 5.3l 300hp hook up turbo spools s480 Borg Warner would be my choice takes off like shot of nitrous with out having to fill the bottle every 3 to 4 hits
 
Buddy's BMW is 6 cylinder single turbo 550hp on the rollers 93 octane fun car light less then around 2400lbs. 10k into engine and turbo setup. 4 bander turbo stang 300hp. That is what is on the street every where.
 
I will try an engine simulation in a while.
Old DD2000 I have.
Post results.

Agree Turbo Boost works.
Extreme Fab work is required.
TIG Welding all.
To pay someone your looking at $2k to start.
Typical $5-10k.
Can rig it but looks like crap and will have leaks under boost.
 
The tooling required to pull off a clean Single or Twin Turbo job magazine quality is expensive.
About $50k.
Know that from Crazy Ed and his garage.
It's a Fiasco business to be in.
Guys are cheep $.
 
9.3 :1 static compression does not seem like alot for modern aluminum heads Grumpy.
I will enter try it.
See what results are.
 
Back
Top